Holmes takes Anna to the pharmacy building, gives her the tour, leads her to his office, and locks her in his vault. He listens as she knocks on the door and walls of the vault. All the while, Anna thinks she is accidentally shut in there and that Holmes has left room for a moment. Her panic increases, and Holmes enjoys what he hears. He then fills the vault with gas and kills Anna.
Afterwards, he goes back to the flat and tells Minnie it is time to go and that Anna is waiting at the pharmacy for them. They ride the train to the building.
A couple of days later, the people who rented the flat to Holmes and Minnie receive a letter from Holmes saying that they no longer need the flat. Holmes calls on a man who makes a living transporting furniture. Holmes has a box and a trunk to haul, and he tells the man to deliver the box to the train station and the trunk to his friend who makes skeletons. Holmes gives the Williams sisters' belongings to his friends, including Pietzel's wife and children.
While the reader actually experiences Holmes's killing Anna, the reader does not witness Minnie's murder through the book's narrative. This technique gives Larson's fiction a nonfictional and historical feel, suggesting that Larson constructs historically accurate events based on his research.
The image of the trunk that foreshadows Anna's death in previous chapters resurfaces during Holmes's latest evil doing. The body in the trunk likely is Anna's.